title: Rotational deviation of 3-acetyl group from cyclic tetrapyrrole pi-plane in synthetic bacteriochlorophyll-a analogs by 20-substitution.
abstract: The 3-acetyl groups of synthetic methyl pyropheophorbides were rotated around the 3-3(1) bond and the rotational conformers were obtained in a dichloromethane solution of 20-bromo- and methyl-substituted compounds, based on their electronic and vibrational absorption spectra. Such a rotational deviation of the 3-acetyl group from the cyclic tetrapyrrole plane induced less pi-conjugation to affect the redmost Q(y) band, which has been observed in natural photosynthetic antenna systems, bacteriochlorophyll-a molecules in oligopeptides.
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Science and Engineering, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan. tamiaki@se.ritsumei.ac.jp
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Tamiaki
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kotegawa
authors.forename: Keisuke
authors.initials: K
authors.lastname: Mizutani
mesh_terms: D025541:Bacteriochlorophyll A / Q000138:chemical synthesis* / Q000737:chemistry; D004563:Electrochemistry; D045342:Light-Harvesting Protein Complexes / Q000737:chemistry; D015394:Molecular Structure; D013329:Structure-Activity Relationship; D045725:Tetrapyrroles / Q000737:chemistry*
chemical_list: D025541:Bacteriochlorophyll A; D045342:Light-Harvesting Protein Complexes; D045725:Tetrapyrroles